Current Role of Blood and Urine Biomarkers in the Clinical Care of Adults with Congenital Heart Disease

The Artificial Intelligence-Enhanced Echocardiographic Detection of Congenital Heart Defects in the Fetus: A Mini-Review

Artificial intelligence (AI) is rapidly gaining attention in radiology and cardiology for accurately diagnosing structural heart disease. In this review paper, we first outline the technical background of AI and echocardiography and then present an array of clinical applications, including image quality control, cardiac function measurements, defect detection, and classifications. Collectively, we answer how integrating AI technologies and echocardiography can help improve the detection of congenital heart defects. Particularly, the superior sensitivity of AI-based congenital heart defect (CHD) detection in the fetus (>90%) allows it to be potentially translated into the clinical workflow as an effective screening tool in an obstetric setting. However, the current AI technologies still have many limitations, and more technological developments are required to enable these AI technologies to reach their full potential. Also, integrating diagnostic AI technologies into the clinical workflow should resolve ethical concerns. Otherwise, deploying diagnostic AI may not address low-resource populations' healthcare access disadvantages. Instead, it will further exacerbate the access disparities. We envision that, through the combination of tele-echocardiography and AI, low-resource medical facilities may gain access to the effective detection of CHD at the prenatal stage.

Blood Biomarkers as a Non-Invasive Method for the Assessment of the State of the Fontan Circulation

The Fontan operation has become the primary palliative treatment for patients with a functionally univentricular heart. The population of patients with Fontan circulation is constantly growing and aging. As the number of Fontan patients surviving into adulthood increases, there is a clear need for research on how best to follow these patients and manage their complications. Monitoring blood biomarkers is a promising method for the non-invasive assessment of the Fontan circulation. In this article, we provide a comprehensive review of the available evidence on this topic. The following biomarkers were included: natriuretic peptides, red blood cell distribution width (RDW), cystatin C, high-sensitivity C-reactive protein, vitamin D, parathyroid hormone, von Willebrand factor, carbohydrate antigen 125, lipoproteins, hepatocyte growth factor, troponins, ST2 protein, galectin-3, adrenomedullin, endothelin-1, components of the renin-angiotensin-aldosterone system, norepinephrine, interleukin 6, tumor necrosis factor α, and uric acid. We did not find strong enough data to propose evidence-based recommendations. Nevertheless, significantly elevated levels of brain natriuretic peptide (BNP)/N-terminal prohormone of BNP (NT-proBNP) are most likely associated with the failure of the Fontan circulation. The use of the RDW is also promising. Several biomarkers appear to be useful in certain clinical presentations. Certainly, robust longitudinal, preferably multicenter, prospective studies are needed to determine the sensitivity, specificity, evidence-based cut-off values and overall predictive value of different biomarkers in monitoring Fontan physiology.

High-sensitive troponin T and N-terminal pro-B-type natriuretic peptide independently predict survival and cardiac-related events in adults with congenital heart disease

AIMS

High-sensitive troponin T (hs-TnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and C-reactive protein (CRP) are established prognostic biomarkers for cardiovascular (CV) morbidity and mortality and frequently used in symptomatic and/or hospitalized adults with congenital heart disease (ACHD). Their prognostic value in clinically stable ACHD has not yet been well established. This study investigates the predictive value of hs-TnT, NT-proBNP, and CRP for survival and CV events in stable ACHD.

METHODS AND RESULTS

In this prospective cohort study, 495 outpatient ACHD (43.9 ± 10.0 years, 49.1% female) underwent venous blood sampling including hs-TnT, NT-proBNP, and CRP. Patients were followed up for survival status and the occurrence of CV events. Survival analyses were performed with Cox proportional hazards regression analysis and Kaplan-Meier curves. During a mean follow-up of 2.8 ± 1.0 years, 53 patients (10.7%) died or reached a cardiac-related endpoint including sustained ventricular tachycardia, hospitalization with cardiac decompensation, ablation, interventional catheterization, pacer implantation, or cardiac surgery. Multivariable Cox regression revealed hs-TnT (P = 0.005) and NT-proBNP (P = 0.018) as independent predictors of death or cardiac-related events in stable ACHD, whilst the prognostic value of CRP vanished after multivariable adjustment (P = 0.057). Receiver-operator characteristic curve analysis identified cut-off values for event-free survival of hs-TnT ≤9 ng/L and NT-proBNP ≤200 ng/L. Patients with both increased biomarkers had a 7.7-fold (confidence interval 3.57-16.40, P < 0.001) higher risk for death and cardiac-related events compared with patients without elevated blood values.

CONCLUSION

Subclinical values of hs-TnT and NT-proBNP are a useful, simple, and independent prognostic tool for adverse cardiac events and survival in stable outpatient ACHD.

REGISTRATION

German Clinical Trial Registry DRKS00015248.

Biomarkers for heart failure and prognostic prediction in patients with Fontan circulation

A wide variety of pathologies are involved in heart failure in patients with congenital heart disease (CHD). Specific causes of heart failure after the Fontan procedure include not only single-ventricle circulation, but also the function of the right ventricle as the systemic ventricle, atrioventricular or semilunar valve stenosis or regurgitation, pulmonary hypertension, and left ventricular dysfunction secondary to right ventricular enlargement or dysfunction. As heart failure can occur post-Fontan, for a variety of reasons, clarification of the pathophysiology is the first step in management and treatment. At the same time, it is important to understand each patient's current condition and treatment plan to make an accurate prognosis. Because of the wide variety of pathophysiologies in post-Fontan CHD patients, however, no single biomarker is useful in all situations. Relevant biomarkers must be selected according to each patient's disease state, and combinations of multiple biomarkers should also be considered. In this review, the author describes the clinical importance of various biomarkers for patients who have undergone a Fontan procedure.

Prognostic value of non-acute high sensitive troponin-T for cardiovascular morbidity and mortality in adults with congenital heart disease: A systematic review

BACKGROUND

Elevation of high-sensitivity troponin-T (hs-TnT) is linked to cardiovascular morbidity and mortality. However, its prognostic value for survival and cardiovascular events and its relation to clinical characteristics and cardiac function parameters in clinically asymptomatic adults with congenital heart disease (ACHD) needs further exploration.

METHODS

A systematic literature search was performed in PubMed and Cochrane from 2010 to May 2020 for hs-TnT as a prognostic marker in ACHD. Three independent reviewers evaluated the articles according to the Study Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies of the National Heart, Lung, and Blood Institute. Overall, eight studies with a total of 2162 ACHD patients (18-63 years) were included.

RESULTS

Hs-TnT level was elevated in 8-26% of asymptomatic ACHD. The follow-up for all-cause mortality and cardiovascular events ranged from 3.0 to 5.6 years and in 8-38% of the participants cardiac endpoints were reached. Throughout the included studies, elevated hs-TnT was found to be an independent predictor for survival and heart failure in stable ACHD. Serial hs-TnT measurement was found to be beneficial over single measurement. Hs-TnT levels were correlated with male sex, higher age, and higher New York Heart Association class and associated with several cardiac dysfunction parameters.

CONCLUSION

More scientific research investigating the prognostic value of hs-TnT in stable ACHD is needed and the clinical relevance to guide aftercare has still to be determined.

Prevalence and Prognostic Association of a Clinical Diagnosis of Depression in Adult Congenital Heart Disease: Results of the Boston Adult Congenital Heart Disease Biobank

Background In adults with acquired heart disease, depression is common and associated with adverse outcomes. Depression may also be important in adults with congenital heart disease (CHD). Methods and Results We conducted a cohort study of outpatients with CHD, aged ≥18 years, enrolled in a prospective biobank between 2012 and 2017. Clinical data were extracted from medical records. Survival analysis assessed the relationship between depression, defined by a history of clinical diagnosis of major depression, with all-cause mortality and a composite outcome of death or nonelective cardiovascular hospitalization. A total of 1146 patients were enrolled (age, 38.5±13.8 years; 49.6% women). Depression had been diagnosed in 219 (prevalence=19.1%), and these patients were more likely to have severely complex CHD (41.3% versus 33.7%; P=0.028), cyanosis (12.1% versus 5.7%; P=0.003), and worse functional class (≥II; 33.3% versus 20.4%; P<0.0001), and to be taking antidepressant medication at time of enrollment (68.5% versus 5.7%; P<0.0001). Depression was associated with biomarkers indicative of inflammation (hsCRP [high-sensitivity C-reactive protein], 1.71 [25th-75th percentile, 0.82-4.47] versus 1.10 [0.45-2.40]; P<0.0001) and heart failure (NT-proBNP [N-terminal pro-B-type natriuretic peptide], 190 [92-501] versus 111 [45-264]; P<0.0001). During follow-up of 605±547 days, 137 participants (12.0%) experienced the composite outcome, including 33 deaths (2.9%). Depression was associated with increased risk for both all-cause mortality (multivariable hazard ratio, 3.0; 95% CI, 1.4-6.4; P=0.005) and the composite outcome (multivariable hazard ratio, 1.6; 95% CI, 1.1-2.5; P=0.025), adjusting for age, sex, history of atrial arrhythmia, systolic ventricular function, CHD complexity, and corrected QT interval. Conclusions In adults with CHD, major depression is associated with impaired functional status, heart failure, systemic inflammation, and increased risk for adverse outcomes.

Angiopoietin-2 predicts morbidity in adults with Fontan physiology

Morbidity in patients with single-ventricle Fontan circulation is common and includes arrhythmias, edema, and pulmonary arteriovenous malformations (PAVM) among others. We sought to identify biomarkers that may predict such complications. Twenty-five patients with Fontan physiology and 12 control patients with atrial septal defects (ASD) that underwent cardiac catheterization were included. Plasma was collected from the hepatic vein and superior vena cava and underwent protein profiling for a panel of 20 analytes involved in angiogenesis and endothelial dysfunction. Ten (40%) of Fontan patients had evidence of PAVM, eighteen (72%) had a history of arrhythmia, and five (20%) were actively in arrhythmia or had a recent arrhythmia. Angiopoietin-2 (Ang-2) was higher in Fontan patients (8,875.4 ± 3,336.9 pg/mL) versus the ASD group (1,663.6 ± 587.3 pg/mL, p < 0.0001). Ang-2 was higher in Fontan patients with active or recent arrhythmia (11,396.0 ± 3,457.7 vs 8,118.2 ± 2,795.1 pg/mL, p < 0.05). A threshold of 8,500 pg/mL gives Ang-2 a negative predictive value of 100% and positive predictive value of 42% in diagnosing recent arrhythmia. Ang-2 is elevated among adults with Fontan physiology. Ang-2 level is associated with active or recent arrhythmia, but was not found to be associated with PAVM.

A new machine learning technique for an accurate diagnosis of coronary artery disease

BACKGROUND AND OBJECTIVE

Coronary artery disease (CAD) is one of the commonest diseases around the world. An early and accurate diagnosis of CAD allows a timely administration of appropriate treatment and helps to reduce the mortality. Herein, we describe an innovative machine learning methodology that enables an accurate detection of CAD and apply it to data collected from Iranian patients.

METHODS

We first tested ten traditional machine learning algorithms, and then the three-best performing algorithms (three types of SVM) were used in the rest of the study. To improve the performance of these algorithms, a data preprocessing with normalization was carried out. Moreover, a genetic algorithm and particle swarm optimization, coupled with stratified 10-fold cross-validation, were used twice: for optimization of classifier parameters and for parallel selection of features.

RESULTS

The presented approach enhanced the performance of all traditional machine learning algorithms used in this study. We also introduced a new optimization technique called N2Genetic optimizer (a new genetic training). Our experiments demonstrated that N2Genetic-nuSVM provided the accuracy of 93.08% and F1-score of 91.51% when predicting CAD outcomes among the patients included in a well-known Z-Alizadeh Sani dataset. These results are competitive and comparable to the best results in the field.

CONCLUSIONS

We showed that machine-learning techniques optimized by the proposed approach, can lead to highly accurate models intended for both clinical and research use.

Evaluation and Management of the Child and Adult With Fontan Circulation: A Scientific Statement From the American Heart Association

It has been 50 years since Francis Fontan pioneered the operation that today bears his name. Initially designed for patients with tricuspid atresia, this procedure is now offered for a vast array of congenital cardiac lesions when a circulation with 2 ventricles cannot be achieved. As a result of technical advances and improvements in patient selection and perioperative management, survival has steadily increased, and it is estimated that patients operated on today may hope for a 30-year survival of >80%. Up to 70 000 patients may be alive worldwide today with Fontan circulation, and this population is expected to double in the next 20 years. In the absence of a subpulmonary ventricle, Fontan circulation is characterized by chronically elevated systemic venous pressures and decreased cardiac output. The addition of this acquired abnormal circulation to innate abnormalities associated with single-ventricle congenital heart disease exposes these patients to a variety of complications. Circulatory failure, ventricular dysfunction, atrioventricular valve regurgitation, arrhythmia, protein-losing enteropathy, and plastic bronchitis are potential complications of the Fontan circulation. Abnormalities in body composition, bone structure, and growth have been detected. Liver fibrosis and renal dysfunction are common and may progress over time. Cognitive, neuropsychological, and behavioral deficits are highly prevalent. As a testimony to the success of the current strategy of care, the proportion of adults with Fontan circulation is increasing. Healthcare providers are ill-prepared to tackle these challenges, as well as specific needs such as contraception and pregnancy in female patients. The role of therapies such as cardiovascular drugs to prevent and treat complications, heart transplantation, and mechanical circulatory support remains undetermined. There is a clear need for consensus on how best to follow up patients with Fontan circulation and to treat their complications. This American Heart Association statement summarizes the current state of knowledge on the Fontan circulation and its consequences. A proposed surveillance testing toolkit provides recommendations for a range of acceptable approaches to follow-up care for the patient with Fontan circulation. Gaps in knowledge and areas for future focus of investigation are highlighted, with the objective of laying the groundwork for creating a normal quality and duration of life for these unique individuals.

Impact of the Fontan Operation on Organ Systems

In patients having undergone the Fontan operation, besides the well discussed changes in the cardiac, pulmonary and gastrointestinal system, alterations of further organ systems including the hematologic, immunologic, endocrinological and metabolic are reported. As a medical adjunct to Fontan surgery, the systematic study of the central role of the liver as a metabolizing and synthesizing organ should allow for a better understanding of the pathomechanism underlying the typical problems in Fontan patients, and in this context, the profiling of endocrinological and metabolic patterns might offer a tool for the optimization of Fontan follow-up, targeted monitoring and specific adjunct treatment.